1. Technical Field
The present invention relates to a flat type stapler in which pointed end portions of a staple are bent flat after it has penetrated, for example, sheets of paper to be fastened together.
2. Background Art
A stapler is stationery for fastening together sheets of paper and is one of inevitable office materials. There have been proposed many staplers. In staplers, there are two types of staplers: one is a type in which pointed end portions of a stapler are bent in a curved fashion after it has penetrated sheets of paper to be fastened together, and the other type is a flat type in which pointed end portions of a stapler are bent flat after it has penetrated sheets of paper to be fastened together.
A general flat type stapler includes a base portion having a clincher, a magazine for accommodating strips of staples, a handle that is pivotally attached to rotate to a position on the base portion which lies in the vicinity of one end thereof, a driving blade which is disposed at a distal end portion of the handle for driving a staple in the magazine towards the clincher in association with the rotation of the handle, a table which has a clincher surrounding portion and performs a clinching operation by raising and lowering the clincher surrounding portion relative to the clincher, a slider made slidable in such a manner as to permit a lowering operation of the clincher surrounding portion at a predetermined timing in relation to the clinching operation by the table and a slider pushing member which is fixed to the handle in such a manner as to cause the slider to slide when the handle rotates.
The stapler configured as described above is such that when a distance between the handle and the base portion is reduced by gripping the handle and the base portion altogether, since the slider push member causes the slider to slide, a locked state of the table and the slider is released, whereby the table lowers, and a staple is pressed between the driving blade and the clincher in such a manner that pointed ends thereof are bent so as to fasten together sheets of paper.
In addition, Japanese Examined Utility Model Publication No. 63-43027 and Japanese Examined Utility Model Publication No. 2-48229 propose staplers in which a clincher is made up of two rotatable members. In these staplers, when a distance between a handle and a base portion is narrowed, the clincher rotates in such a manner that an upper portion of the clincher is made into a flat plane so as to bend flat pointed ends of a staple.
In staplers, there are two types of staplers: one is a hand-held stapler and the other is a desktop stapler. A desktop stapler has substantially the same basic construction as that of a hand-held stapler but is larger in size than the hand-held stapler. In addition, since the weight of the user is exerted on to a handle member to lower the handle member in such a state that the stapler is placed on a desk or the like at its base portion, a large number of sheets of paper can be fastened together at one time.
In the desktop stapler that has been described above, although a large magnitude of force becomes necessary to fasten together a large number of sheets of paper, since the handle is pivotally attached to rotate to a position on the base portion which lies in the vicinity of a rear end thereof, when such a large magnitude of force is applied to the vicinity of a distal end of the handle, there has been caused a problem that the rear end of the stapler is raised. In addition, in order to solve this problem, there is a method in which the base portion is formed long at the front thereof, but this has triggered another problem that the base portion is enlarged.